Shelf



FIG. 1 is a perspective view of a shelf, showing my new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a left side elevation view thereof;

FIG. 5 is a right side elevation thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a bottom plan view thereof;

FIG. 8 is an exploded perspective view thereof;

FIG. 9 is a perspective view of part of the shelf in an alternate configuration; and,

FIG. 10 is a perspective view of part of the shelf in an alternate configuration. 

CLAIM The ornamental design for a shelf, as shown and described. 